#include <iostream>

using namespace std;

typedef long long LL;

const int N = 1e5 + 10;

int n, q;
LL a[N];
LL f[N];


int main()
{
	cin >> n >> q;
	for(int i = 1; i <= n; i++)
	{
		cin >> a[i];
	}
	for(int i = 1; i <= n; i++)
	{
		f[i] = f[i-1] + a[i];
	}
	while(q--)
	{
		int l, r;
		cin >> l >> r;
		cout << f[r] - f[l - 1] << endl;
	}
	return 0;
}
